[en] This is the text of an introductory talk on phenomenal consciousness (University of Liège, 6 october 2011). I give a historical-critical reconstruction of the framework within which the issue has developed, focusing on its metaphysical-epistemological dimension. Sections: 1- Historical Background: Main Paradigms in the Philosophy of Mind; 2- Phenomenal Consciousness: Preliminary Clarifications; 3- Overview of Some "Classical" Strategies; 4- What's Wrong With Qualia? (Historical Excursus); 5- The Knowledge Argument; 6- Objections to the Knowledge Argument; 7- Conclusion